1. Field of the Invention
The present invention relates to a small-sized portable information terminal apparatus which is used for handling mail, parcels, slips, etc. having various kinds of information placed on their surfaces by hand-writing, printing or the like, and which has various functions such as fetching a surface image of a subject, reading a character or barcode written on the surface of the subject, storing necessary information, displaying necessary information, making communication with an external device, etc.
2. Description of the Related Arts
In the business of the delivery of mail and in the distribution industry, rationalization has been attained by controlling the flow of subjects such as mail, freight, etc. on the basis of information obtained by reading characters or barcodes attached to the subject. Heretofore, apparatus for extracting information by reading characters and the like has required complex mechanism, so that the apparatus must be installed at a fixed place. Accordingly, the reading of information placed on the subject is generally performed at a fixed point such as a point on a belt conveyor in a freight depot.
However, the most efficient delivery can be made when information on the destination of the subject is known at the time of acceptance of the subject. Further, it is preferable that the path of delivery can be confirmed at a midpoint of the delivery by comparing information written on a slip or the like attached to the subject with delivery control information. Further, if the description of the type of packing at the time of acceptance and the destination of the subject is maintained on a sheet, the sheet may be used as evidence should an accident occur during transit or a dispute arise between a customer and a deliverer.
In the mail delivery service and in the distribution industry, therefore, a portable apparatus for easily reading and processing characters or the like attached to mail or freight in an arbitrary place is needed, in order to designate, control and confirm the transportation flow at the place of acceptance of the mail or freight or an arbitrary midpoint of delivery.
Conventionally, there is a portable information terminal apparatus in which characters or barcodes attached to a surface of a subject by handwriting or printing is read by sensing the surface of the subject taken in hand.
For example, in JP-A-3-142580, Kawanowa et al. has disclosed a portable data terminal apparatus having an image inputting function for acquiring information by reading a barcode printed on a surface of an article, storing, displaying and communicating the information. In the apparatus disclosed by Kawanowa et al., a surface of an article as a subject is illuminated so that image data is acquired by a CCD area image sensor through a reflection mirror and a lens, digitized to be stored, and decoded to be transmitted to an external device through a communication line. The portable data terminal apparatus disclosed by Kawanowa et al. using area image sensors can read out characters and barcodes written on a slip attached to the surface of the subject as a two-dimensional image without the movement of the apparatus relative to the subject. The image data fetched can be indicated on a display device incorporated in the apparatus and also be transmitted to an external device through a communication line.
In the aforementioned apparatus, however, sharp images can be obtained only when the optical system meets a strict condition. In order to decode the barcode correctly or read the characters correctly, it is therefore necessary to support the apparatus so that the apparatus maintains a predetermined correlation with the subject while an image is fetched. Because the apparatus is to be handled by an operator using his hands, a window is provided so that the operator can check the position of the apparatus relative to the subject by the use of his eyes. It is still difficult even for an operator skilled in the art to fetch a sufficiently sharp image. Further, because a printer for obtaining a hard copy of the result of reading the image is located at a remote external device, the hard copy cannot be supplied to the client as evidence for the accepted job.